Report of the Smoke Abatement Committee 1882 : with reports of the jurors of the exhibition at South Kensington, and reports of the testing engineer to which are added the official reports on the Manchester exhibition.

  • Smoke Abatement Committee.
Date:
1883
Catalogue details

Licence: Public Domain Mark

Credit: Report of the Smoke Abatement Committee 1882 : with reports of the jurors of the exhibition at South Kensington, and reports of the testing engineer to which are added the official reports on the Manchester exhibition. Source: Wellcome Collection.

    185/384 (page 163)
    Table XXXIII.—GREGORY'S FURNACE FOR STEAM BOILERS versus THE ORDINARY BOILER. Data Gregory furnace connected to boiler Ordinary boiler Do. do. per hour Ash Do. consumed ...... Do. consumed per hour ..... May 1, 1882 8 hours 188£ lb. 23-56 lb. £ lb. 25^ lb. 67-5° Fahr. 1 19 cub. ft. ] 1185-6 lb. 2-375 cub. ft, 6-29 lb. May 2, 1882 8 hrs. 21 min. 229£ lb. 27-50 lb. 2£ lb. 5 lb. 62° Fahr. 19 cub. ft. ] 185-6 lb. 2-28 cub. ft. 5-17 lb. Period during which smoke was visible Average smoke-shade for the whole period of trial 18 min. No. 1 0-04 6 hrs. 40 min. No. 8 2-86 These results show practically an entire freedom from smoke for the Gregory furnace, and for the boiler with the ordinary furnace an average smoke-shade nearly No. 3, whilst the maximum was No. 8. The quantity of water evaporated per pound of coal with the Gregory furnace was upwards of 20 per cent, more than without it. No. 5. Thomas Henderson.—Mechanical Stoker: for firing small coal or slack. The slack is charged into a hopper, in which it is crushed, as required, and carried downwards by a revolving toothed roller, which beats opposite a pressure-plate. The width of the clearance between the roller and the plate is regulated by means of a screw, for the purpose of regulating the feed of coal to the furnace. The coal is dropped upon two horizontal fans or propellers, formed with fins, by which the fuel is propelled into the furnace upon the fire-grate. The fans are caused to revolve on vertical spindles, by friction- wheels, which are below them and support them; the wheels being keyed on a horizontal transverse shaft driven by means of worms and worm-wheels, by power from a small engine, placed near the boiler. The furnace-bars are reciprocated by means of a rocking crank- motion, in which there are two sets of cranks at right angles. Whilst every alternate bar rises and falls | inch above and f inch below the regular level, the intermediate bars have a longitudinal movement of 1 inch to and fro, in order to break up clinker as it is formed, and carry it backward over the bridge, and to cause the coal to travel backward as it burns. (Plate 72.) Mr. Henderson's stoker is at work on several boilers at the Dean Clough Mills of Messrs. Crossley, Halifax. The boilers are 1\ feet in diameter, and 23^ feet in length, having two flues 3 feet in diameter. The grates are 3 feet 10 inches in length, having a com- bined area of 23 square feet. It is stated that 5 tons per day of Charlston nut-slack can be burned off; but that 3^ tons is as much as can properly be consumed in a day of 9| hours, being at the rate of nearly 1\ cwt. per hour. From official returns of the results of special tests at Dean Clough Mills it appears that 6*70 lbs. of water was evaporated per pound of nut-coal from the temperature of 50° F. into steam of 70 lbs. pressure per square inch, by hand-firing; and that 8*31 lbs. of water was evaporated per pound of nut-coal from the temperature 184° F. into steam of the same pressure, with the mechanical stoker. Making due allowance for the higher temperature of the feed-water, the equivalent quantity of water evaporated from 50° F., with the mechanical stoker, is 7*10 lbs. per pound of coal, being 6 per cent, more than was evaporated with hand-firing. Henderson's mechanical stokers, at work on the three Cornish boilers at the Surrey